Fluid pressure tool



G. M. NELL FLUID PRESSURE TOOL Filed Aug. 17. 1929 Sept. 29, 1931.

2 Sheets-Sheet 1 A TTORNE Y.

Sept. 29', 1931. n G. M. NELL 1,825,328

FLUID PRESSURE TOOL Filed Aug. 17. 1929 2 Sheets-Sheet 2 7t 9 31 29" 74 ze a 31 2 30 35 27 v fg zal: '[51 l# @We MW A TTORNE Y.

Patented Sept. 29, 1931 d @UNITED lS'LMEs PATENT OFFICE GUSTAVE NELL, OF DETROIT, MICHIGAN, ASSIGNOR TO CHICAGO PNEUMATIG TOOL COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY FLUID :PRESSURE Toor.

Application med August 17, 1929, serial No. 386,52s.

' `This Vinvention relates to fluid pressure during the drilling operation.l

-, bottom of theV drill hole drills ofthe percussive type and moreparticularly to forms of the samejwhichiprovide for: blowing the cuttings out of the drill hole In certain aspects it maybe considered as an'improve-v ment upon, or further development of, the invention disclosed in my copending application SerialNo; v)1t,893,1iiled October 25,

One object ofthe invention is'to provide fluid pressure vmeans'under manual control to maintain the moving parts ofthe tool in positions such as to pass pressure fluid to the lOther objects will be apparent from the detailed description which follows.

` In order to illustratethe invention one concrete embodiment thereof is shown in the ac- 'companying` drawings in which:

Fig. 1 is a top plan View; v

yFig. 2 is a sectional view substantially on the line 2-2 of Fig. 1 but showing the drill steel in elevation;

Fig. 3 is an end elevational view of the cylinder of the tool after the back head has been'removed; i u v -Figs 1 and 5 are fragmentary sectional views on` the line 4-4 of Fig'. 3, Ashowing the manual control valve in different positions;

and

Fig. Gis a fragmentary sectional view substantially on the line 6-6 of Fig. 3.

The embodiment of the invention, chosen for the purpose of illustration, comprises a fluid pressure .percussive-tool or rock generally conventional in form, having a cylinder`7 providing a piston chamber 8 within which reciproca-tes a hammer'piston 9 having an extension 9a adapted to deliver blows to a hollow drill steel 10 supported in the front head 11of the drill. Piston`9 carries at its rearward end a rifle nut 12 which cooperates with a. rifle bar 13 having bearings in cylinder ring 14 and back head 15 and with the dan,

usual ratchet arrangement in the back head. The rotation imparted to piston 9 by the rotation mechanism, is transmitted by splines or ribs 9c on piston extension 9a to chuck 16 which receives the polygonal shank of drill steel 10.v The grooves between ribs 9c permit the passage of motive iuid from'the forward end of piston chamber 8 to the bore 10a of the drill steel to blow out 'the cuttings when the piston is in its rearward position. A water tube 17 of conventional form, mounted in back head 15 and extending through axial bores in riflebar 18 and piston 9, may feed water into bore 10a of the drill steel to assist in washing out the cuttings and to eliminate dust. The cylinder is provided with a main exhaust chamber 18 substantially centrally thereof andcontrolled by the head of piston 9 on its reciprocations.

An automatically thrown valve 19, whichis Vof the same general form as that disclosed in my aforesaid copending application, distributes the pressure fluid, admitted by throttle valve 20 actuated by handle 21, to the opposite ends of the piston chamber. Valve 19pis tubular in form with end areas-of differential extent continuously subjected to motive fluid, the larger end area being remote from the fluid inlet. A shoulder 22 is subjected to. air trapped and compressed by piston 9 on its rearward stroke for moving the valve forwardly, and such compressed air may be augmented, if desired, by live motive iiuid in limited amount escaping through a small port 23 in the valve itself To throw the'valve in the rearward direction, the same is provided with an annular flange 24, one face of which is continuously vented .to atmosphere through a port 25, the opposite face 24a of greater extent than the combined areas of shoulder 22 and the adjacent or smaller end area being intermittently supplied with motive fluid from the pisthe piston. A vent passage 27' of smaller capacity than supply passage 26 is provided for relieving the pressure on area 24a. A vent passage 28 also leads from the rear end of the piston chamber 8. The purpose of these last named vent passages and the inanner of controlling the saine will presently be described.

To permit blowing out the drill hole as desired, a manually operated valve of any suitable or desired type is provided for controlling inain exhaust 18 as well as vent passages 27 and 28. rlhe valve 29 herein shown (F igs, 1 and 3-6) is of the Corliss or cylindrical type which is supported for rotation or oscillation in a projection 7a on the cylinder casing the bore of which niaybe lined, if desired, by a bushing 30. `A spring handle 31 straddles projections 7a to retain valve 29 in place, and to provide manual means for oscillating the same, suitable sockets, such as 32, receiving the sides of handle 81 yieldinglyto maintain the'same in adjusted position. For normal drilling operation handle 31 is disposed in the position indicated in Figs. 1, et, and 6 wherein an arcuate recess 29a (Fig. 4) in the valve establishes communication between the main exhaust groove 18 for the piston chamber and an exhaust port 33 in the cylinder casing. In this position a bore 29o through valve in spaced rela-tion to recess 29a also establishes communication between the restricted venting passage 27 for valve shift area 251e (Figs. 2, 3, and 6) and an exhaust port 84,

lVhen it is desired to blow the cuttings out of the drill hole, handle 31 of' manual exhaust valve 29 is pulled back until its sides snap into sockets 82, the valve being then 1n the position shown in Fig. where both main exhaust 18 and valve vent 27 are closed. Vent passage 28 leading to therear end of the piston chamber is then put in communication with exhaust port 33 by the arcuate recess 29a in the valve, Pressure will then be maintained against rearward valve shift area 24a since it cannot escape through passage 27, and valve 19 will be maintained in the position shown in Fig. 2. It desired, a small live air port 85 may be provided in the valve (Fig. 2) to replace any leakage and positively to prevent forward movement of the valve. Since live air continuously passes to the forward end of the piston chamber, the piston will be held in its rearward position (not shown), thus exposing the grooves in piston extension 9a and permitting the live air to pass down the bore 10a of the drill steel to blow the cuttings out of the drill hole. Pressure cannot develop against shift shoulder 22 of valve 19 since all pressures in the rear end of' the piston chamber including that admitted through port 23 in the valve passes to atmosphere through vent passage 28. On throwing exhaust valve handle 31 to the forward position, (Fig. 1) the tool will resume its normal drilling operation.

While the invention has been herein disclosed in what is now considered to be a preferred forni, it is to be understood that the having an atmospheric exhaust port for said piston chamber under control of said and means including a normally open vent for one of' the pressure areas of said valve and manually operated means for simultaneously opening and closing both said vent and said exhaust port, thereby at will to dispose said piston in position to permit pressure fluid to pass along the grooves thereof to the hollow drill steel.

2. In a fluid pressure percussive tool', a cylinder providing a piston chamber, a piston reciprocable therein and provided with an extension having grooves,rmeans for sup-l porting a hollow drill steel to receive the blows of said piston, an automatically thrown valve for controlling the distributionof motive fluid for actuating said piston, and means including a normally open vent for one of the pressure areas of said valve and a normally closed vent for the rear end of said piston chamber, and manually operated means for controlling said vents.

3. lny a fluid pressure percussive tool, a cylinder providing a piston chamber, a piston reciprocable therein and provided with an extension having grooves, means for supporting a hollow drill steel to receive the blows of said piston, an automatically thrown valve for controlling the distribution of motive fluid for actuating said piston, said cylinder providing a area of said valve and a vent for the rear end of said piston chamber and a main exhaust port controlled by said piston, and a single manually operated valve for controlling said vents and said exhaust port.

4.. In a fluid pressure percussive tool, a cylinder providing a piston chamber, a piston reciprocable therein and provided with anextensioii having grooves, means for supporting a hollow drill steel to receive the blows of said piston, an automatically thrown valve for controlling the distribution of motive fluid for actuating said piston, said cylinder providing a vent for a pressure area of said valve and a vent for the rear end piston,

vent for a pressureof said piston chamber and a main exhaust port controlled by said piston, and a single manually operated valve for controlling said vents and said exhaust port, said last named valve in one position establishing connection of said valve vent and of said main eX- haust with atmosphere and in another position cutting olf the same and connecting said piston chamber vent to atmosphere.

5. In a fluid pressure percussive motor in combination, a cylinder providing a piston chamber, a piston reciprocable therein, and an automatically thrown valve for controlling the distribution of motive fluid for actuating said piston, said valve being tubular and arranged to receive the motive fluid therewithin and to control its access to said piston chamber by the ends thereof, said ends of said valve presenting differential end areas, said valve having an additional pressure area adjacent the smaller of said differential areas and always in communication with one end of the piston chamber so as to be subject to air compressed by the piston at one end of its stroke thereby to assist the pressure of the live motive fluid upon the smaller of said differential end areas to overcome the pressure onthe opposed larger differential area thereby to shift the valve, and manually controlled vventing means for said end of said piston chamber. l

6. In a fluid pressure percussive motor in combination, a cylinder providing a piston chamber, a piston reciprocable therein, and

an automatically thrown valve for controlling the distribution of motive fluidfor actuating said piston, said valve being tubular and arranged to receive the motive fluid` therewithin and to control its access to said piston chamber by the ends thereof, said ends of said valve presenting differential end areas, said valve having an additional pressure area adjacent the smaller of said differential areas and always in communication with one end of the piston chamber so as to be subject to air compressed by the piston at one `end of its stroke, said valve having a fourth pressure area of greater extent than said additional area and the smaller of said differential areas when combined and for overcoming the latter, means admitting mo- Y tive fluid continuously in limited amount to said fourth area of said valve, and means under control of said piston for admitting motive fluid from said piston chamber to said fourth area of said valve.

7. In a fluid pressure percussive motor in combination, a cylinder providing a piston chamber, a piston reciprocable therein, and an automatically thrown valve for controlling the distribution of motive fluid for actuating said piston, said valve being tubular and arranged to receive the Inotive fluid therewithin and to control its access to said piston chamber by the ends thereof, said ends of said valve presenting differentialend areas', saidvalve having `an additional pressure area adjacent the smaller of'said differential'area's and always in communication with one end of thepiston chamberso as to be subject to air compressed by the piston at one end of itsstrolre, said'valve having a fourth pressure area of greater extent than said additional area and the smaller of said differential areas when combined and for overcoming the latter, Vmeans under control of said piston for admitting motive areas, said valve having an additional pressure area adjacent the smaller of said differential areas and always in communication with one end of the piston chamber so as to be subject to air compressed by the piston at one end of its stroke, said valve having a fourth pressure area of greater extent than said additional area and the smaller of said differential areas when ycombined and for overcoming the latter, means admitting motive fluid continuously in limited amount to said fourth area of said valve, means under control of said piston for admitting motive fluid from said piston chamber to said fourth area of said valve, and manually controlled venting means for said fourth area;

9. A fluid pressure percussive motor comprising a cylinder providing apiston chamber, a piston reciprocable therein, said cylinder providing an exhaust chamber having a vent to atmosphere substantially centrally of said piston chamber and arranged to be overrun by Vsaid piston, an automatically thrown distributing valve moving in timed relation with said piston for controlling the movements of the latter, said cylinder providin an exhaust passage extending to the rear en of said piston chamber and a vent passage extending to a pressure area of said valve, and a manually actuated valve for controlling communication of both said passage and of said exhaust chamber with atmosphere. j

' l0. A fluid `pressure percussive motor comprising a cylinder providing a piston chamber, a piston reciprocable therein, an automatically thrown distributing-valve moving in timed relation with sai'd piston for controlling the movements of the latter, said Valve having a pressure area for effecting its movement in one direction, said cylinder providing a vent passage extending to said pressure area of said valve and an exhaust passage extending to the rear end of said piston Chamber, and a manually actuated valve for controlling communication of both said passages with atmosphere.

Signed by nie at Detroit, in the county of Wayne, and State of Michigan this 13 day of August, 1929.

GUSTAVE M. NELL. 

